Steam-engine.



N0. 660,562. Patented 001. 30,1900;

J. DAVIDSON & T. R. HAMPSON.

STEAM. ENGINE.

(Application filed. June 6, 1899.)

1N0 Model.) 3 Sheets-Sheet l ATTORNEYS m: uonms Pntna 60.. momma.wAsmNo'ron. 0. c4

No. 660,562. Patented Oct. 30, I900. J. DAVIDSON &. T. R. HAMPSON.S-TEAM ENGINE.

(Application filed June 6, 1899.)

(No Mqdel.) 3 Sheets$haet 2.

ATTORNEYS The worms Pzrzns so. mow-Luna, WASHINGTON. o. c

No. 650 562. Patented Oct; 30, I900.

J. DAVIDSON 8:. T. R. HAMPSON. STEAM ENGINE.

(Application filed June 8, 1899.) (No Model.)

I 3 Sheets-Sheet 3.- Q lb. [0 M6 45/ %W 4/ U W W? M i 1- 1 1 A i a X l 7E A TTORNE Y5 THE cams PETERS co, PMOYO-LITNQ, WASHINGTON, u. c.

NlTED STATES PATENT OFFICE.

JOHN DAVIDSON, OFECOLES, AND THOMAS REGINALD HAMPSON, OF CHESTER,ENGLAND.

STEAM-ENGINE.

SPECIFICATION forming part of Letters Patent N 0. 660,562, dated October30, 1900.

Application filed June 6,1899- berial No. 719,591. (No model.)

To all whom it may concern;

Beit known that We, JOHN DAVIDSON,a resident of Eccles, and THOMASREGINALD HAMP- SON, a resident of Chester, England, subjects of theQueen of England, have invented certain new and useful Improvements inSteam- Engines, of which the following is a specification.

This invention has reference mainly to steam-engines of the triplecompound type that is to say, an engine in which the expansion of thesteam is carried out in three separate cylinders of successively-largerdiameter.

The object of the invention has been chiefly to construct an engine thatwill give an eventurning eifort to the shaft and at the same time to bevery simple yet economical and be capable of running at high speed, and,furthermore, to so arrange and operate an engine of this type that onlyone steam-distribution valve and valve-gear is required and used.

Theimprovementsinstearn-engines according to our invention areillustrated in the accompanying drawings, and they will be described bythe aid of these drawings, the same letters of reference being used inthe several viet's representing the different modifications to denotethe same or equivalent partswherever they occur.

In the drawings, Figure l is a sectional elevation showing adouble-acting engine provided with our improvements. Fig. 2 is asectional elevation illustrating our improvements as applied to asingle-acting engine. Fig. 3 shows a modification of a duplex tandemengine according to ourinvention. Fig. a shows a modification under theinvention, in which the intermediate and low pressure cylinders are inannular arrangement. Figs. 5, 6, 7, 8, 5 6, 7, and 8 are diagrammaticviews illustrative of the relative positions of pistons and ports of thehigh-pressure and intermediate-pressure cylinders and different relativepositions of the cranks at different points of the strokes in the caseof the'singleacting engine shown in Fig. 2.

Referring now to the drawings, and in the first instance to Fi l, a, 'i,and 0 are highpressure, intermediate pressure, and lowpressurecylinders, respectively, of the engine, and a, i, and 0 are the pistonsof these three cylinders, respectively.

b is the one steam-distribution valve of the engine distributing steamto the high-pressure cylinder. In the case shown this valve is of thepiston type, the upper and lower heads or ends of which work over and inconnection with the steam-ports c and have a tubular stem b connectingthem together. Steam is' introduced into' the annular space d of thevalve-case d, about the tubular part b of the valve, the steam-lap ofthe pistons of the valve being on their inside edges, and the spacewithin the valve and the ends of the valve-case constitute thereceiver-space to this the first cylinder of the engine.

The pistons of the cylinders are connected to their respective cranks bypiston-rods and connecting-rods in anysuitable or known way.

The piston a of the high-pressure cylinder a is a double piston, thepart between the piston-heads of which is of smaller diameter and formsan annular passage or port about it. The exhaust-steam from the cylinderat is controlled by the piston a, and the flow from this cylinder to theintermediate-pressure cylinder is by way of ports 6, the openings ofwhich into the cylinder at (which, say, extend all around) are governedby the pistonheads a, while the space f about the central portion ofthese piston-heads and the cylinder-casings communicating with itconstitutes the receiver to the intermediate cylinder. The openings ofthe ports e out of the cylinder (1 are near the ends of the stroke ofthese pistons a in the opposite ends of the cylinder Ct, and theopenings of the ports e into the opposite ends of the cylinder '11 areat the outer ends of this cylinder. The piston i of this intermediatecylinder is an elongated double-headed piston and serves to control thesupply of exhaust-steam from its cylinder't' to the low-pressurecylinder 0,'the poi-ts communicating between t' and 0 being designatedj. The piston t" is similar to a,

and the central part joining the two heads is of reduced diameter andconstitutes a passage, serving as an exhaust-passage in the cylinderfrom the low-pressure cylinder 0 to an opening 7t, (shown in dottedlines in the.

cylinder 2,) constantly open to this annular port of i. Thesteam-portsj, as will be seen, are short and lead directly from thecylinder 7, to the cylinder 0. Consequently the clearance capacity issmall and waste of steam in the low-pressnre-cylinder ports avoided.

In action when the high-pressure piston ct is at the extreme end of itsstroke at one end of the cylinder at the steam-port c belonging to thatend is uncovered by the head of the piston-valve b and steam-enters thecylinder and the supply is continued for the desired portion of thestroke of the highpressure piston when it is cut off by the valve. Thenwhen the cylinder approaches the outer end of its strokesay about thepoint as illustrated in the crank diagram in Fig. 5 and also shown inFig. 5one of the piston-heads a uncovers one of the ports e and steam exhausts from a to one end of the ends of the intermediatepressurecylinder t', and this communication is continued until the highpressurepiston has reached a certain point in the upward strokeviz., the pointat which opening commenced when it closes this port 6 and the steamadmitted to expands. This point of cut-off will be about thatrepresented in Figs. 6 and 6. Then the steam in '6 expands until thepiston has reached a point, as shown in Fig. 7, which is equivalent inits stroke to the point reached by the crank ot' theintermediate-pressure piston, (shown in Fig. 7,) when it uncovers one ofthe portsj and the steam exhausts from i into the low-pressure cylinder0, the piston of this cylinder being at or near the end of one of itsstrokes. This communication will continue during the portion of thestroke of 0 until a point in the return stroke of z" is reached whichcorresponds to the point at which the opening to o commenced, when it iscut off and expands. When the piston 0 has reached the end of itsstroke,the cylinder 0 will be put in communication with the exhaust-portZ- and the opening by the uncovering of the p'ortj by the inner edge ofthe piston '11. This communication is maintained until the piston 0' hastraveled the greater portion of its stroke, when compression commences.During a portion of the return stroke of the high-pressure pistonanamely, from about the point indicated in Figs. 6 and 6 the piston willbe compressing into the receiver-that is,the space inside the valve 19and the ends of the valve-case 61-- and when this communication is outOE and steam supplied from the annular port dthe opposite end of thecylinder at will then be put in communication with the internal space ofb, which acts as the receiver then for. this end.

With regard to the exhaust from the nonactive end of theintermediate-pressure piston 11, while steam is acting at the oppositeend on the piston this end will be in communication with the spaces f,and that for a portion of its stroke the entrance of the port 6 will beuncovered to the inner edge of the piston-body a at that end, and itwill remain open until this inner edge closes it, when compression in c'commences. The steam is compressed until the end of the stroke of thepiston 1." is reached, when the steam from the high-pressure cylinderpasses from it into 2'. The duration of this compression depends uponthe length of the piston-bodiesa and the proportion of the stroke whichit takes in moving between the point at which e is closed by the inneredge of the piston-body and that when the opening of it takes place bythe outer edge of the piston-body. Then, with regard to the operationswithin the low-pressure cylinder on the side of the piston which is notbeing acted on by steam, the steam will be exhausted by way of the port7', the annu-' lar space around the intermediate part between thepiston-heads t", and the outlet 76, for the greater part of its stroke,when the portj will be closed by the inner edge of one of the ends ofthe piston t" and compression in 0 will take place until this port isopen to one of the ends of the cylinder 1' by its being uncovered by theback edge of 2".

Obviously the exact degree in the relative positions of the three cranksand pistons of this engine at which the openings and closings of theseveral ports take place may vary to a considerable degree; but we willnow describe and trace, as an example, the distribution of steam and theperiods in the strokes of the several pistons at which admission,release, closing, compression,'and other factors in the completeoperation in the engine with regard to steam distribution from the pointof admission of steam of full pressure to that of the discharge from thelow-pressure cylinder. This example, of course, will be within thelimits of the range of variations at which these several actions andfunctions can take place, and its employment will give a satisfactoryand economical result as a whole and throughout the engine. The enginein connection with which these complete operations will be described isa double-acting threecrank engine, as illustrated in Fig. 1.

With regard to the relative arrangement of cranks, assuming theintermediate-pressurecyliuder crank to be taken as the one in re lationto which the others are to be considered, then the high-pressure crankmay lead the intermediate-pressurecylinder crank by about one hundredand twenty-seven degrees and the intermediate-pressure crank will leadlthe low-pressure crank by about one hundred %and thirty-two degrees ofthe circle. The jlead of the low-pressure over the high-pressurecylinder will therefore be one hundred and one degrees.

First, with regard to the admission of steam Zto the high-pressurecylinder. This is under gthe control of the valve 1) and its admissionland operation may take place in the usual ,way, and it may therefore beadmitted and cut off at the cylinder-ports c at practically any point,or it may also, if desired, be under ICC ICO

the control of an automatic shaft-governorf Assuming, then, so much, thebehavior, actions, &c., of the various pistons acting as valves in thedistribution and manipulation of the steam throughout the engine willnow be specified.

High-Pressure Piston as the valve of the Intermediate Cylinder.

' steam-opening.

Bottom e-ncl.-'lhe piston a opens port e to the intermediate-pressurecylinder at seventy-six per cent. of upstroke and closes the port attwenty-four per cent. of downstroke, this end of the cylinder being opento the receiver for the remaining portion of the stroke, as justdescribed.

Inte7"mediate-Pressur-e Cylinder.

Top enrZ.-Steam enters from high-pressure cylinder forsiXty-fivepercent. of downstroke, when it is cut off by the high-pressure piston.The steam then expands for a period, and at eighty-two per cent. of itsdownstroke it opens the portj to the low-pressure cylinder, and it-thatis, the piston t"-closes this port at about 17.5 per cent. in itsupstroke. The opening to the receiver of the other end of the cylindermay take place simultaneously with the opening of the low-pressurecylinder, in which case the compression will take place during 6.25 percent. of the stroke of the piston, or this opening to the receiver maytake place at a point representing ninety per cent. of the stroke, in'which case the compression will be about fifteen percent. of the stroke.

Bottom end.-Steam enters this end from the high-pressure cylinder forsixty per cent. of the stroke of t. It is then cut off, and subsequentlyat seventy-six per cent. of the stroke of 2" it opens the port j to thelow-pressure cylinder, and then closes. this port at twenty-four percent. of its downstroke. The compression. in this cylinder will be fiveper cent. of the stroke in the case of the opening to the receiver,being simultaneous with the opening to the low-pressure cylinder, andfifteen per cent. compression if the opening to the receiver takes placeat ninety-two per cent. of the stroke.

Low-Pressure Cylinder.

Top cnd.--Steam from the intermediatepre ssure cylinder enters thiscylinder for sixty-six per cent. of thestroke of its piston, when it iscut off from intermediate-pressure cylinder by the piston t closing theport j. It then expands, and at ninety-two per cent.

of the stroke it is released and passes away by the port Z and annularspace around the piston to the outlet 7c, and the compression at the endof the stroke will be fifteen per cent.

Bottom end-With regard to this end of this cylinder the cut-off,release, and compression will be sixty per cent., ninety-three percent., and fifteen per cent, respectively, of the stroke.

Referring now to the modification shown in Fig. 2, this shows asingle-acting engine having the main general characteristics andarrangements of the engine shown in Fig. 1. In this case the admission,distribution, and exhaust of the steam to and from the several cylindersin their active strokes may be taken to be substantially similar tothat'set forth with reference to Fig. 1; but the idle or nonactive endsof the cylinders in this case are somewhat modified, and they are asfollows: The receiver to the high-pressure cylinder and piston is thespace within the casing d and within the tubular part b of the valveb-that is, the greater parts of the valve-casingand it is in constantcommunication with the lower end of the cylinder ct by the ports 0, theupper steam-port 0 only being controlled by the valve 1). The idle endof the intermediate-pressure cylinder forms a receiver to the upper endof the cylinder, as in the upstroke of the piston a, and during theupstroke of t" the upper end of this cylinder 2' is put in communicationwith the lower end bythe annular passage around the intermediate partofthe piston a, which puts the port 6 in communication with the bottomend of 'i by a port 6. The idle end of the lowpressure cylinder 0 has areceiver or chamber 0 which is always in communication with the exhaust,and at the outer ends of the stroke of the piston 0 this piston byuncovering a port 0 communicating between 0 and the upper side of thecylinder, forms a natural drain for this cylinder.

Figs. 5 5 to 8 8 illustrate, diagrammatic ally, several relativepositions of the pistons of the high and intermediate pressure cylindersduring the moments of important .actions of steam distribution,manipulation, and use in the several cylinders, and the positions of thecranks connected with these cylinders in the stroke corresponding withthese positions. For instance, Figs. 5 and 5 illustrate the point ofexhaust from the cylinder Ct to the cylinder 71, Figs. 6 and 6illustrate the point of cutoff of steam from a to t, Figs. 7 and 7illustrate the point of putting the upper and lower ends of the cylinder1' in communication with each other and so making the cylinder its ownreceiver, while Figs. 8 and 8 illustrate the point at which thiscommunication is cut off and compression in t begins. Figs. 5 to 8 alsoillustrate the controlling action of the intermediate-pressure piston 'iin connection with the admission and exhaust ports j and Z of thelowpressure cylinder 0, showing the periods in the stroke of the piston1." at which these ports j Z are open to the interior of 2', closedwholly by the piston 11, and are in communication with each other whileout of communication with t.

Fig. 4 shows the arrangement of a triple compound engine having adistribution of steam and a mode of action substantially similar to thatset forth with reference to Fig. 2; but the arrangement of the cylindersis different. The low-pressure cylinder 0 instead of being at the sideof the intermediate cylinder Q1 is at once both in tandem arrangementwith it and concentricthat is to say, the cylinder 0 is at a lower levelthan the part of the cylinder 2' which is traversed by the piston t",and the cylinder 0 and piston 0 are annular, the septum between 0 andvlbeing the continuation of the cylinder '5. In this case, as in theothers above described, the exhaust-portj from the intermediate-pressurecylinder to the low-pressure cylinder is short and the clearance in thecylinders 0 is therefore small, and this port is uncovered by the piston6 during the outer portion of its stroke for the exhaust of steam from'1; to 0, while during most of the upstroke prior to closing forcompression the ports j form a communication between the upper part ofthe cylinder 0 and the lower part of both cylinders o'and 2', which arecommon and which are open to the exhaust by means of the pipe is. Inthis case there will be two low-pressure cranks instead of one, as inthe above engines.

The engine shown in Fig. 3 is a modification of the double-acting engineshown in and set forth with reference to Fig. 1. In it in lieu of thesingle intermediate-pressure cylinder two of such cylinders are employedin tandem arrangement one above the other, the pistons 1" being on thesame connecting-rod. In this case the ports 6, communicating with thecylinder a, are bifurcated, one part leading to the upper cylinder andthe other to the lower cylinder. Thus the double piston a of thehigh-pressure cylinder a serves also as a valve for the distribution ofsteam from this cylinder to the two intermediatepressure cylinders i,and in like manner the steam from the cylinders 'i may be distributed intwo other low-pressure cylinders, or, as a modification of this, athree-crank engine with one valve may have one high, one intermediate,and two low pressure cylinders acting in the manner described. Enginesof this latter character under Fig. 3 and its modifications will providea high power with a short length of engine and a small space occupied.

Although the invention has been mainly described as applied to aninverted vertical engine havingthree cylinders side by side, it is notrestricted to this arrangement, as it -may be applied to engines havingdifferent positions and to different relative arrangements in which theexpansion of the steam is carried out in three stages.

What is claimed in respect of the hereindescribed invention is- Incombination in a triple compound steamengine, three cylinders, a, i and0, a valvecasing having a passage at each end leading to the cylinder01,, a tubular valve having heads controlling said passages, a passageleading from the intermediate part of cylinder at to the opposite endsof cylinder 1 a valve in cylinder at having heads for closing saidpassages, an intermediate portion to form a continuation of the saidopening leading directly through the intermediate part of the walls ofcylinder 2' into opposite end of cylinder 0, a piston on said cylinder1' having heads for closing said openings and an intermediate partadapted to put the same in communication with an exhaust-opening, acrank-shaft, a piston in cylinder 0, and pitman connections between saidpiston and said crank-shaft.

In witness whereof we have hereunto set our hands in presence of twoWitnesses.

JOHN DAVIDSON. THOS. REGINALD HAMPSON.

Witnesses:

WILLIAM CASH, JNo. E. WALKER.

